add --csv parameter to skpdiff to dump all scores in a csv file. We can run it with all skps, and h…

experimental/skpdiff/SkDiffContext.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkDiffContext_DEFINED
 #define SkDiffContext_DEFINED
 
@@ skipping 72 matching lines @@
      *             ]
      *         }
      *     ]
      * }
      *
      * @param stream   The stream to output the diff to
      * @param useJSONP True to adding padding to the JSON output to make it cross-site requestable.
      */
     void outputRecords(SkWStream& stream, bool useJSONP);
 
+    /**
+     * Output the records score in csv format.
+     */
+    void outputCsv(SkWStream& stream);
+
+
 private:
     struct DiffData {
         const char* fDiffName;
         double fResult;
         SkTDArray<SkIPoint> fPointsOfInterest;
     };
 
     struct DiffRecord {
         SkString           fBaselinePath;
         SkString               fTestPath;
         SkTArray<DiffData>        fDiffs;
         DiffRecord*                fNext;
     };
 
     // We use linked list for the records so that their pointers remain stable. A resizable array
     // might change its pointers, which would make it harder for async diffs to record their
     // results.
     DiffRecord * fRecords;
 
     SkImageDiffer** fDiffers;
     int fDifferCount;
 };
 
 #endif